Thanks Andrey for providing these links, there are tons of good information there.
I already read a god post by legend Henric Cronström, where I learnt how to create all reference dates for my dates intervals ( date_start and date_finish )
I wondered if there would be a simple script modification to that one already in my app, that could provide all the reference dates between my start and finish dates BUT excluding the weekends ( and optionally holidays ).
I could probably join that table to a master calendar to get my expected result ( as in my excel mockup printscreen )
networkdays(date_start, date_finish) as Work_days,
Date(date_start + IterNo()-1) as date_Fill
While IterNo()<= date_finish - date_start + 1;
Thanks again for your time and help